Trying to diagnose Asiair Pro guiding issues, can someone take a look at the detailed log I have?

[wimvb]

Orientation of the guidecam is unimportant. That’s why you do a calibration. But there is an easy way to align your guidecam. Turn tracking of and take an exposure of at least ten seconds with the guide cam. You should see star trails, mainly in the RA direction. If they are very short, repeat with double the exposure time. Turn your guide camera so that the trails line up with one edge of the sensor.

If dec drift caused guiding to fail, phd would show the message ”star lost”. And you would see a drop in star mass. This is not the case. Poor polar alignment is in my opinion NOT the cause of RA wandering off that quickly. Next time out, do a polar alignment. Then point near the meridian, about 40 degrees up and do a phd calibration. After that, run guiding assistant for at least 10 minutes, preferrably longer. Use the suggested settings, and check polar alignment error. Then start guiding while you sit by the mount. (Let phd choose a star, as long as it is not too close to the edge of the frame) Make sure cables are tidied up or hang free. And of course, make sure the mount is balanced, perhaps slightly heavier on the east side.

Watch the guide graph and take note when RA starts to wander off.

 

Good luck

[Davey-T]

Have you checked PA  with the Star Adventurer polar scope ? it's all I use with mine, if you use an app to set it you can them monitor it during imaging to see if Polaris stays tracking round the circle and if not do a little tweak to put it back.

Dave

[michael8554]

This is guiding with ASIAir,  PHD2 comparisons may not be valid.......... !

Michael

 

[Jay6879]

On 08/07/2021 at 12:54, Davey-T said:

Have you checked PA  with the Star Adventurer polar scope ? it's all I use with mine, if you use an app to set it you can them monitor it during imaging to see if Polaris stays tracking round the circle and if not do a little tweak to put it back.

Dave

 

Good idea, wish I saw this post past night before gong out. I'll be sure to give it a shot tonight, this looks to be my last clear night for at least a week.

Update, so I did a double polar align last night. Managed my cords better. I attempted to reduce backlash by adjusting the screw on the bottom of the unit. There is no "clicking" backlash sound anymore when I move the unit with the clutch tight and it appears to rotate freely. I left the clutch open and had the counterweights on and it dropped smoothly into the 6o'clock position so I believe it is not too tight?

In the end it didn't make much of a difference at all. It still was going wild after some time. I wasted the night, what a bummer. However, when I was putting away the Zenithstar 61 I noticed the guide scope rail moved...

I was able to wiggle it back and forth a heavy 1/16 of an inch. Not much but I'm assuming it could be enough to mess with guiding? I friggin hope? Seriously, it would be wonderful to tighten that up and everything just work again...

[wimvb]

That explains a lot. Your guidescope should never move relative to the imaging scope.

Also, I’m a bit confused regarding how you have the clutch. When released, the mount should move freely. Correctly balanced, it should stay in any position. If either end falls down, you have an imbalance.

During imaging, you tighten the clutch, but not overtighten it.

[Jay6879]

2 hours ago, wimvb said:

That explains a lot. Your guidescope should never move relative to the imaging scope.

Also, I’m a bit confused regarding how you have the clutch. When released, the mount should move freely. Correctly balanced, it should stay in any position. If either end falls down, you have an imbalance.

During imaging, you tighten the clutch, but not overtighten it.

 

My bad I should've been more clear, when I said 

Quote

 I left the clutch open and had the counterweights on and it dropped smoothly into the 6o'clock position

I meant when I was tightening up the worm adjustment screw. I had read that was a good way to tell if it had been tightened up too much, causing binding. That was done with just just counterweights by themselves. As for the actual balancing with the scope on it I did a little modification allowing me to add a bit more weight and I'm more balanced than I was before.

 

Let's hope tightening that part up solves these issues!

[Jay6879]

On 10/07/2021 at 15:35, wimvb said:

That explains a lot. Your guidescope should never move relative to the imaging scope.

Also, I’m a bit confused regarding how you have the clutch. When released, the mount should move freely. Correctly balanced, it should stay in any position. If either end falls down, you have an imbalance.

During imaging, you tighten the clutch, but not overtighten it.

 

Well, after weeks and weeks of rain and clouds and forest fire smoke, last night I finally got a chance to see if the changes would solve these issues.

 

Swapped in new cables and managed them better to reduce any chance of snags

Modified the counterbalance rod to have a bit more weight for better balance 

Tightened up the loose autoguiding rail

Double (and even triple) polar aligned 

And....the issue still persists. It runs well for awhile then goes wild. I don't get it, I'm feeling utterly dejected at this point. Get a load of this, when the autoguiding WAS working I took a 5 minute and 10 minute test exposure to see how it would do...

 

I zoomed it in to get a better look at the star shape, but that looks pretty damn good to me for 5 minutes at 360mm focal length! During that exposure the RA bounced between 2" and 3" and yet still managed to pull that off?

Next I tried 10 minutes...

At 10 minutes you can see the stars jussst starting to go egg shaped.

But I see this and think to myself, mechanically there isn't an issue? If there was surely it would've shown up. So does it come down to software? I have no friggin idea anymore. I was going to upload the log but for some reason it didn't save it? I'll check again tonight.

 

My next step is to try PHD2 on a laptop and see how that goes. I tried hooking it up but it didn't recognize my guide camera for some reason? Do I need to download those ASCOM drivers? I'm using a Stwr Adventurer, which is st-4 so I was under the impression ASCOM didn't apply.

 

Do you have any other ideas here?

Edited July 22, 2021 by Jay6879

[JSeaman]

Do you have a log file?

Still drifting a lot in Dec?

Did you increase the pulse size?

Although you don't need ASCOM for the mount you still need a driver for the camera (ASCOM or otherwise)

[wimvb]

Testing on a laptop is a good idea. If the problem persists, it must be something mechanical. I would babysit the gear during such a test, and check everything when RA starts to misbehave.

Unfortunately, I don't have any further ideas at the moment.

[Scooot]

Just an idea but I wonder if your polar alignment is moving when you move the scope to the target. I used to have this problem sometimes. 
Are the altitude adjustment screws on the star adventurer very loose, if so the mount could be moving a tad in RA when you move the scope? . And I realise it doesn’t guide in dec, but if I over tightened the dec lever on the little mount it would also move that slightly. 

[Jay6879]

4 hours ago, wimvb said:

Testing on a laptop is a good idea. If the problem persists, it must be something mechanical. I would babysit the gear during such a test, and check everything when RA starts to misbehave.

Unfortunately, I don't have any further ideas at the moment.

 

So those two pics I posted above were 5 and 10 (!) minute exposures using a Zenithstar 61ii, the ten minute one has bloated stars but they are still quite round. The 5 minute exposure looks mint. IF it happens to be mechanical, what should I be looking out for?

 

I just got PHD2 all setup and ready to go. I'll be outside soon to give it a go. I figured I may as well format the Asiair Pro SD card that holds the OS, and then flash the card with the backup I made when I first got the Asiair Pro. I tried to format it and it wouldnt do it. Kept throwing a "windows was unable to format the card" error. Strangely enough it only showed the card as having 30mb of space, despite being a 32gb card.

 

I tried repairing it, just regular ol windows formatting, using disk manager, even going into the cmd prompt and using diskpart to select the volume and manually format that way. It all didn't work. Didn't matter if I formatted in exfat or ntsf it was throwing up errors. I looked at the SD card and it was bent!

 

New card on the left, old on the right. So I'm now flashing the OS backup inmade when I first got the Asiair Pro. I wonder if this is why it wasn't saving any guiding logs as well.

Could this damaged SD card be the cause of my guiding woes? ...ehh..probably not. But as long as I have any new theories to test out I can keep up hope that there will be a solution!

Edited July 23, 2021 by Jay6879

[Jay6879]

5 hours ago, JSeaman said:

Do you have a log file?

Still drifting a lot in Dec?

Did you increase the pulse size?

Although you don't need ASCOM for the mount you still need a driver for the camera (ASCOM or otherwise)

I dont have a log file of the latest (last night's) session as it didn't save one for some reason. The SD card holding the os was bent and damaged and had a bunch of errors when I tried to format it so I'm assuming that is the reason why it didn't save a log. 

 

It didn't seem to be drifting in DEC lime it was before, the two pics above of a 5 and 10 minute exposure show half decent dec. I polar aligned three times 😬

 

I'm not sure how to increase pulse size in Asiair Pro. Is that the same as the "aggressiveness" setting?

 

 

4 hours ago, Scooot said:

Just an idea but I wonder if your polar alignment is moving when you move the scope to the target. I used to have this problem sometimes. 
Are the altitude adjustment screws on the star adventurer very loose, if so the mount could be moving a tad in RA when you move the scope? . And I realise it doesn’t guide in dec, but if I over tightened the dec lever on the little mount it would also move that slightly. 

I actually have that altitude adjustment screws zingin tight at all times, but it still allows some very stiff movement in altitude. That lock screw is so horribly designed. So much slop.

[JSeaman]

A corrupt SD card won't do you any favours

It sounds like you should run the guide assistant in PHD and report back, it should give a good indication of what your issue is

Do you see these:

[wimvb]

4 hours ago, Jay6879 said:

tried repairing it, just regular ol windows formatting, using disk manager, even going into the cmd prompt and using diskpart to select the volume and manually format that way. It all didn't work

I use SD formatter. I'm not at my computer right now, but I believe it's an older version of this

https://www.sdcard.org/downloads/formatter/

I can check tonight, when I'm home again. Btw, if the card works in the asiair,  it's not corrupted or damaged. And it shouldn't be the cause why the log file wasn't saved.  But definitely try to replace it.

4 hours ago, Jay6879 said:

IF it happens to be mechanical, what should I be looking out for?

Any sudden movements, noise or sound, star hopping on screen, etc. At one time, my guiding misbehaved whenever I moved around the rig I was babysitting. Vibrations moved through the ground when I got too close to the mount. I moved the rig from the patio to the lawn, where I drove fence anchors into the ground for the tripod to sit on. I also made sure never to step close to a tripod leg.

Don't assume anything when troubleshooting, work methodically and keep an open eye to details. When the error occurs, you should see the guide star suddenly move on screen.

[Jay6879]

6 hours ago, wimvb said:

I use SD formatter. I'm not at my computer right now, but I believe it's an older version of this

https://www.sdcard.org/downloads/formatter/

I can check tonight, when I'm home again. Btw, if the card works in the asiair,  it's not corrupted or damaged. And it shouldn't be the cause why the log file wasn't saved.  But definitely try to replace it.

Any sudden movements, noise or sound, star hopping on screen, etc. At one time, my guiding misbehaved whenever I moved around the rig I was babysitting. Vibrations moved through the ground when I got too close to the mount. I moved the rig from the patio to the lawn, where I drove fence anchors into the ground for the tripod to sit on. I also made sure never to step close to a tripod leg.

Don't assume anything when troubleshooting, work methodically and keep an open eye to details. When the error occurs, you should see the guide star suddenly move on screen.

I ended up using the new flash card.

So I managed to get a bit of time out there before clouds rolled in. PHD2 was working very well, sub 2" for the most part. Test exposures looked good. The ten minute mark rolled around and the numbers were still great, I was ecstatic. Yet sure enough a few minutes later the numbers blasted off into the hundreds. Ugh. I having this burning fascination in me to image, especially after it working out so well earlier in the spring. I'm feeling quite dejected at this point, not sure where to go from here.

This is the log

PHD2_GuideLog_2021-07-22_203634.txt

I've been reading up on how to properly interpret the log files, and I think I have a basic understanding but I really appreciate all the tips and opinions here trying to figure this out. I'd be completely lost! With more experience these things won't be so foreign to me.

So to recap..

I've got new cords

I've gotten better with cord management, no snags 

Fine tuned balance 

Double and triple polar align

Asiair Pro and PHD2 both showing similar patterns with the issue

When the guiding works, it works fantastically. The issue is why the guiding doesn't consistently work like it did in the past where I'd have it running all night and just sleep. Instead it fails at fairly repeatable intervals. All of my gear sits in a foam lined Nanuk case so I don't think anything is damaged.

I'm feeling utterly dejected with this all. Watching the summer roll on by, all those sweet objects won't be there much longer!

So at this point it HAS to be something mechanical right? Could the worm mesh adjustment screw being too tight or too loose cause this? That's my next step I guess, sit outside with an Allen key and adjust on the fly or something. I dunno, not sure where to go to from here. I hope that log file I posted has some info that could be gleamed from it.

Thanks again everyone for the interest in helping me with this nightmare!

 

[JSeaman]

Have you run the guide assistant? Did you increase the pulse size?

 

I can see massive spikes which the mount is recovering from then it fails at the end:

 

Have you checked your balance in the orientation the scope is on this target? With clutches off does it stay in position?

Guiding of +/- 5 arc seconds I wouldn't be able to image at all, that gives blobby stars for sure

If you sit next to the mount when it goes wrong can you hear the motor driving?

Have you tried leaving it without PHD to see if you get runaway?

[Jay6879]

13 minutes ago, JSeaman said:

Have you run the guide assistant? Did you increase the pulse size?

 

I can see massive spikes which the mount is recovering from then it fails at the end:

 

Have you checked your balance in the orientation the scope is on this target? With clutches off does it stay in position?

Guiding of +/- 5 arc seconds I wouldn't be able to image at all, that gives blobby stars for sure

If you sit next to the mount when it goes wrong can you hear the motor driving?

Have you tried leaving it without PHD to see if you get runaway?

 

I didn't get a chance to run the guide assistant last night as clouds came in, same with changing the pulse size. I planned on doing one run with everything default then another matching the pulse size I set for calibration on the Asiair Pro (8000ms). That is the pulse size you're are taking about correct?

When I balance I point it in the general direction I'll be imaging, and it stayed in position yes.

Maybe I'm ok with +/-5" cause the scope is only 360mm? Like I showed with the images I posted the other day, it still seems to be within a workable parameter.

The whole time I was sitting there babysitting the setup and yeah I could hear the motors whirring away. 

Your last question I don't think I've done lately, beyond leaving the tracker running while I am focusing, or while I'm calibrating the guiding. The last time it would've ran like that was before I got the guide camera setup and I don't recall any major drifting issues at all.

 

As for the graph up there, those two big spikes are strange, but like you said it recovers. Not sure what would've caused that, then randomly off to the right "star lost".

Ugh.

[JSeaman]

I'd definitely be inclined to do the guide assistant, it can reveal a multitude of issues

Pulse size change might make it react to the point it can catch it but there's an underlying issue to find

Yes, 8000 is quite big but fair enough

Cool, so if it's well balanced you will be able to nudge it around in RA and DEC and it will stay put - worth checking you can do that in a few places. Even the weight of cables can make a difference but the issue you have feels like something larger!

Yes your focal length will be a factor but I was at <1" with 450mm 

So does the motor start driving the scope when it runs away?

I'd definitely be inclined to give it 20 minutes running by itself and see what happens. You can potentially do that when it's cloudy too as long as you can measure the movement somehow

The star loss looks like a symptom, the mount moves so the star goes but the RA runaway happens first and the SNR of the star is good right up until then

[Jay6879]

25 minutes ago, JSeaman said:

I'd definitely be inclined to do the guide assistant, it can reveal a multitude of issues

Pulse size change might make it react to the point it can catch it but there's an underlying issue to find

Yes, 8000 is quite big but fair enough

Cool, so if it's well balanced you will be able to nudge it around in RA and DEC and it will stay put - worth checking you can do that in a few places. Even the weight of cables can make a difference but the issue you have feels like something larger!

Yes your focal length will be a factor but I was at <1" with 450mm 

So does the motor start driving the scope when it runs away?

I'd definitely be inclined to give it 20 minutes running by itself and see what happens. You can potentially do that when it's cloudy too as long as you can measure the movement somehow

The star loss looks like a symptom, the mount moves so the star goes but the RA runaway happens first and the SNR of the star is good right up until then

 

You were able to get sub 1" at 450mm on a Star Adventurer? That's awesome, something to look forward to then eh. I had set it to 8000ms as that's what I had read is a good match for the 120mm guide scope I have?

Tonight looks stellar so I should be able to continue this saga, if I do the guiding assistant will there be a log I could upload here? I did a quick Google search and it looks quite complex. But I will give it a shot. I'll also let the Star Adventurer run on its own for 20 minutes or so and take screenshots of the Asiair to show any drifting, which I suspect there will be SOME considering the periodic error of these mounts.

As for when the scope runs away yeah, if j remember correctly I could hear the motor going. I just can't remember if I heard the motor continuously humming away or if it was jn pulses or what.

When you say this..

Quote

The star loss looks like a symptom, the mount moves so the star goes but the RA runaway happens first and the SNR of the star is good right up until then

Could the RA runaway be due to the gears having huge manufacturing imperfections or something? Like I said before, I was able to use this thing just fine unguided and guided for quite some time before this issue popped up so I never gave it much thought.

[JSeaman]

No sorry 450mm guide scope and PHD2 not a StarAdventurer

Good luck tonight, hopefully you can narrow things down further. The guide assistant is definitely a great place to start and will tell you what it finds, just ping up a screenshot

I think the 20 minute drift will be interesting too

You'd have to have some pretty sever imperfections. Try slewing the mount a long way on highest speed and see whether it is smooth

[Jay6879]

32 minutes ago, JSeaman said:

No sorry 450mm guide scope and PHD2 not a StarAdventurer

Good luck tonight, hopefully you can narrow things down further. The guide assistant is definitely a great place to start and will tell you what it finds, just ping up a screenshot

I think the 20 minute drift will be interesting too

You'd have to have some pretty sever imperfections. Try slewing the mount a long way on highest speed and see whether it is smooth

 

I'll check back tomorrow with whatever new data I can acquire then! As it stands I haven't hit a wall yet, there are still leads to follow so I'm not feeling completely done. There is hope yet! Almost as much as I just want to start imaging I want to find out what could possibly be the cause of this. Considering it happens in PHD2 and the Asiair Pro it kinda suggests that software isn't the issue. 

Ah well, let's see what happens tonight eh. Thanks for helping me out here!

[JSeaman]

Hey no problem, we've all been there. The night you accept you're going to spend the whole time solving the problem it tends to go away Just be methodical and you'll figure it

[wimvb]

I had a look at your guide log. The good news is: you're getting good at polar alignment. The bad news: the log doesn't give any new insights. The mount has a large periodic error (at least 50 arcseconds peak to peak), but that guides out very well. As you wrote, after some 10 - 15 minutes the mount just wanders off, and guide pulses have no further effect. My first thought when I saw the graph was; perhaps something is gradually working its way free, but because the pattern repeats with the next guide period, you would have to fasten whatever that was, and you'd know it. I also briefly thought that dew might have something to do with it. But the same goes here; because it repeats, the dew would have to be away for a while.

Next time out, you could try letting the guide assistant run for some 20 minutes, just to check if the mount veers off again. Other than that, I'm out of ideas. But, if you have the possibility, take an image of your gear and post it here. Maybe that will turn up something.

[Davey-T]

Have you tried starting in different positions ? ie camera higher than the weight to see if it affects the time between issues.

No harm in giving it a little helping push in the right direction to see if it helps put it back on track.

Dave

[Jay6879]

1 hour ago, wimvb said:

I had a look at your guide log. The good news is: you're getting good at polar alignment. The bad news: the log doesn't give any new insights. The mount has a large periodic error (at least 50 arcseconds peak to peak), but that guides out very well. As you wrote, after some 10 - 15 minutes the mount just wanders off, and guide pulses have no further effect. My first thought when I saw the graph was; perhaps something is gradually working its way free, but because the pattern repeats with the next guide period, you would have to fasten whatever that was, and you'd know it. I also briefly thought that dew might have something to do with it. But the same goes here; because it repeats, the dew would have to be away for a while.

Next time out, you could try letting the guide assistant run for some 20 minutes, just to check if the mount veers off again. Other than that, I'm out of ideas. But, if you have the possibility, take an image of your gear and post it here. Maybe that will turn up something.

Oh boy, this all doesn't sound very promising at all!

No dew though, I have some dew heater strips. I haven't gone outside yet, its not quite dark and some clouds have moved in. Hoping they clear but this is my setup...

 

 

Don't mind the taped but of extra weight, I've since changed the setup to something more elegant (kjnda) that allows much better balance, and obviously cords haven't been tidied up yet in the pic but that's essentially it.

 

I wonder if anyone else has had issues like this? I've tried searching but it's such a broad subject to be searching. It may not be on the level of these crazy mounts and telescopes I see but it still was a half decent chunk of dough you know? Kinda crappy that it's such a pain.

Well hopefully it clears out soon so I can run the guide assistant.

 

 

 

Edited July 24, 2021 by Jay6879